It is proposed to use data from the Collaborative Perinatal Project of the NINDS to determine if abnormalities in the placenta can serve as predictors of long term neurologic, sensory and cognative abnormalities in children. The study collected sequential neurologic, cognative and sensory data on children from the newborn period to eight years of age. We examined nearly 35,000 placentas from this NINDS study to standardize the recognition and recording of specific abnormalities. In addition, more than l000 pieces of clinical information were prospectively collected for most of the cases. Included were data on events of gestation, labor, delivery and the neontal period. We propose to correlate each of the long list of placental abnormalities with a battery of test data detailing children's psychomotor, cognative and sensory abnormalities and development starting in the neonatal period. Several methods will be used to determine if the associations between placental findings and neurobiologic impairments revealed by the analyses are biologically valid or are the result of chance or of the interactions of more than l00 non-placental factors that can affect psychomotor and sensory development. These methods include: (a) log linear model analysis of 3-way contingency tables, (b) discordant sibling pairs, (c) longitudinal analyses of children with and without developmental abnormalities, (d) cross validation determined by analyzing half of the data base and then replicating the analyses on the second half of the data base.